1) Field of the Invention
The invention herein relates to a single-actuation, synchronous dual closure structure disc brake device having a single brake cable actuated bidirectional-type thrust cylinder driver that enables the achievement of an inner brake pad and an outer brake pad arranged at two sides capable of synchronous, opposing travel, and equalized force, and double-sided brake clamping operation.
2) Description of the Prior Art
The comparatively numerous single-actuated type disc-type brake device now utilized in the industrial world consists of a mounting plate 2 installed onto a fork leg having the bolt 21 situated horizontally through its lateral surface providing for a brake cable 31 that pulls and releases a fixed axis, reciprocating, and pivoting lever 32 to control axial rotation for the inward end-surfaced extension and retraction of a single-direction travel thrust cylinder driver 33 of a movable base 3. Of which, the said thrust cylinder driver 33 has installed at its interior side and end surface an outer brake pad 341, with an inner stop surface 3A situated at the rear extent and extending from the same movable base 3 that provides for the installation of another inner brake pad 342 at its interior lateral surface, thereby enabling the respective positioning at the two sides of a brake disc 4 and the forming of a brake clamping arrangement (as shown in FIG. 1-A).
In this type of device, when the interior side and end surface of the thrust cylinder driver 33 is impelled to extend in front section travel, the outer brake pad 341 is pushed inward and first brought pushing against the outer side of the brake disc 4 to achieve the first phase of partially closed clamp braking operation at the outer disc surface (as shown in FIG. 1-B).
When the typist cylinder driver 33 continues to be driven and thus extend in rear section travel, the outer brake pad 341 continues being pushed inward and, due to blockage posed by the brake disc 4, it can only proceed in the opposite direction and the movable base 3 moves laterally outward in backward movement such that the inner brake pad 342 at the interior face of the inner stop surface 3A correspondingly moves outward in forward movement and then positioned pushing against the outer side of the brake disc 4 to achieve the second phase of fully closed clamp braking operation at the inner disc surface (as shown in FIG. 1-C).
Although such a structure is capable of executing a double surfaced clamping closure at the two sides of the brake disc 4, the timing difference as the two brake pads are brought into closure one after another results in physical application at unequal force and a loss of frictional balance and, in addition to precluding efficient and precise braking operation, each instance the outer brake pad 341 is first pushed outward towards the brake disc 4, the thin-type brake disc 4 becomes inclined slightly inward after protracted utilization and, furthermore, its service life is correspondingly reduced. As such, manufacturers must utilize a brake disc of greater thickness to overcome this; however, such utilization results in a brake disc that has the shortcomings of heavier weight, excessive space occupance, and increased production cost.
Another more improved structure is a kind of double-actuated type disc brake device (as shown in FIG. 2-A), its difference being the installation of a pair of mounting bases 51 and 52 at the two sides of a brake disc 4 and external hydraulic lines 511 for pulling and releasing and thus controlling at its interior section single-direction thrust cylinder drivers 512 and 522 that have respectively installed at their interior sides and end surfaces outer and inner brake pads 513 and 523 for opposingly faced, laterally inward, end-surfaced extension and retraction travel control.
In such devices, the two thrust cylinder drivers 512 and 522 are inner laterally, end-surfaced, and synchronously driven into extension, with the outer and inner brake pads 513 and 523 thereby brought synchronously against the two sides of the brake disc 4 to execute closure (as shown in FIG. 2-B). Although the two-sided, synchronous, and opposed closure at the brake disc 4 disc surfaces is advantageous in that no skewing occurs, the pair of thrust cylinder drivers 512 and 522 results in greater cost, additional malfunctions, and other related problems; for example, fluid leakage from the hydraulic thrust cylinder drivers 512 and 522 easily occurs, resulting in reduced pressure or pressure losses that lead to pressure imbalances inside the two lateral tubes and, furthermore, the pressure impelling the outer and inner brake pads 513 and 523 becomes unequal, with the pressure at the two sides of the brake disc 4 similarly unequal such there is the shortcoming of non-synchronous application during clamping closure.
The primary objective of the invention herein is a single bidirectional thrust cylinder driver installation in which during the synchronously and axially oriented extension of the two lateral end surfaces, an outer brake pad at the interior lateral surface of an inner motion guide sleeve is moved inward from an outer motion guide sleeve backward to a -shaped moveable caliper base, causing the movement of the inner brake pad situated vertically at its interior surface; furthermore, in the said assembly constituted, the inner brake pad is actuated into operation by a single brake cable and simultaneously completes an opposing and synchronous clamping operation to achieve at the two sides of the brake disc at the center section an equalized force and bidirectional closure that is balanced, stable, and precise in brake clamping operation.
Another objective of the invention herein is a single bidirectional thrust cylinder driver that synchronously and with an equalized force actuates the inward closure and return of two laterally-disposed outer and inner brake pads such that the brake disc is kept vertical to facilitate equal friction at the outer and inner brake pads to decrease overall friction and thereby prolong device operation and durability and, furthermore, save space, lighten weight, and be more economically feasible.
Yet another objective of the invention herein is a single bidirectional thrust cylinder driver that actuates the inward closure and return of two laterally-disposed outer and inner brake pads that achieves more operational efficiency than conventional double thrust cylinder driver synchronous double-closure devices and compared to single thrust cylinder drivers is structurally simpler, easier to fabricate and susceptible to fewer malfunctions, and thus more economical and practical.
The structural utilization, operation, and other aspects of the present invention are elaborated in the following detailed description of the invention herein.